Suk Myung Eun
Mechanical Engineering, IT Convergence College of Components and Materials Engineering, Dong-Eui University, Busan, South Korea.
Nanoscale Res Lett. 2020 Nov 2;15(1):204. doi: 10.1186/s11671-020-03436-4.
Recent advances in the development of two-dimensional (2D) materials have facilitated a wide variety of surface chemical characteristics obtained by composing atomic species, pore functionalization, etc. The present study focused on how chemical characteristics such as hydrophilicity affects the water transport rate in hexagonal 2D membranes. The membrane-water interaction strength was tuned to change the hydrophilicity, and the sub-nanometer pore was used to investigate single-file flux, which is known to retain excellent salt rejection. Due to the dewetting behavior of the hydrophobic pore, the water flux was zero or nominal below the threshold interaction strength. Above the threshold interaction strength, water flux decreased with an increase in interaction strength. From the potential of mean force analysis and diffusion coefficient calculations, the proximal region of the pore entrance was found to be the dominant factor degrading water flux at the highly hydrophilic pore. Furthermore, the superiority of 2D membranes over 3D membranes appeared to depend on the interaction strength. The present findings will have implications in the design of 2D membranes to retain a high water filtration rate.
二维（2D）材料开发的最新进展促进了通过原子种类组成、孔功能化等获得的多种表面化学特性。本研究聚焦于亲水性等化学特性如何影响六方二维膜中的水传输速率。调节膜与水的相互作用强度以改变亲水性，并使用亚纳米孔来研究单分子流，已知这种单分子流具有出色的盐分截留能力。由于疏水孔的去湿行为，在低于阈值相互作用强度时水通量为零或极小。高于阈值相互作用强度时，水通量随相互作用强度的增加而降低。通过平均力势分析和扩散系数计算发现，在高亲水性孔中，孔入口的近端区域是降低水通量的主要因素。此外，二维膜相对于三维膜的优势似乎取决于相互作用强度。本研究结果将对设计保持高水过滤速率的二维膜具有启示意义。
